This invention relates to an image/audio reproducing system for receiving the image and the audio and being arranged on the head of a user.
Heretofore, reproduction of the feeling of reality in an image/audio reproducing system has been mainly by a large-format screen and by enlarging the system size by multi-speaker reproduction. Recently, an image/audio reproducing device 100, made up of a head attachment type image display unit 101 of a reduced size and an audio reproducing unit 102 annexed to the unit 101, as shown in FIG. 1, has come into use with a view to conforming to personal taste and reduction in size.
The image display unit 101 is driven by a driving circuit 104, supplied with a video input signal from a video input terminal 103, for displaying an image, as shown in FIG. 2.
The audio reproducing unit 102 amplifies an audio input signal, entering an audio input terminal 105, by amplifiers 106L, 106R, and transmits the amplified signals to a headphone speaker for left ear 107L and a headphone speaker for right ear 107R, for the furnishing the audio to the user, as shown in FIG. 2.
Since the audio reproducing unit 102 localizes the sound image within the head of the user, the audio is not matched to the image displayed on the video display unit 101, so that the feeling of reality cannot be reproduced spontaneously.
For overcoming this drawback, attempts have been made in updating the image and the audio on a real-time basis responsive to the body movements and in convolving the sound field to get close to the feeling of reality by, for example, a digital signal processing unit, for regenerating the viewing/hearing environment close to reality.
In these attempts, voluminous signal processing is required particularly in audio processing, such that the image/audio reproducing apparatus cannot be reduced to a size for attachment to the head. In addition, a motion detector tends to be costly.
If the sound image can be localized outside the head such that a sound field feeling close to reality can be achieved, but the video system is moved in the viewing/hearing environment to follow up with the head movement as heretofore, significant deviation is produced between the sound image position and the visual image position, thus resulting in non-spontaneous image/audio reproduction.
If the image contents are updated depending on head movements using a special source, both the video system and the audio system become increased in size and become costly.